Friction shock-absorbing mechanism



21 1927. June J. F. o'coNNoR FRICTION SHOCK ABSORBING MECHANISM Original Filed June 8. 1925 2 Sheets-Sheet l` 1,63 ,o 4 June, 2.1, 1927. J' F. @CONNOR l 3 3 FRICTION SHOCK ABSORBING MEGHANISM Original Filed June 8. 1925 2 Sheets-Sheet 2 M ffy well-known form.

ramadan 21,1921. o

UNITED STATES PATENT OFFICE.

JOHN F. OGONNOB, OF CHICAGO, ILLINOIS, ABSIGNOB TOW. H. m3, INC., Ol'

CHICAGO, ILLINOIS, A CORPORATION Ol' DELAWARE. y

,FBICTION SHOCK- ABSOBBING HECHANIBH.

application mea :une '8, 1925, seran A*This invention relates to improvements in friction shock absorbing mechanisms.

One object of the invention is to provide a friction shock absorbing mechanism especially adapted for railway draft riggings, having graduated action during compression of the mechanism, the graduated action including relatively light initial resistance followed by progressively increased resistance.

Another object of the invention is to provide in a mechanism'of the character indicated, a plurality of relatively movable fric-v .tion plates and a friction wedge system,

wherein the friction wedge system is movable initially with reference to the plates to effect relatively light resistance and all of the parts are movable as a unit, together rigging, showing my improvements in connection therewith, the section through the friction shell and elements therewithin being taken on two section planes 120o apart. Figure 2 is a front end, elevational view of the shock absorbingmechanism proper. Figure 3 is a vertical, transverse, sectional view corresponding substantially to the line 13-3 of Figure 1. And Figure 4 is a detailed, perspective view of a curved friction plate used in connection with 4my improved mechanism. In said drawings, -10 indicate channelshaped center ordraft sills of'a railway car underframe, to the inner vfaces of which are secured front stop lugs 11-11 and rear stop lugs 12-12. The inner end portion of the drawbar is designated by 13, to which is operatively connected a hooded yoke 14 of The shock absorbing mechanism proper, as ivellas front and rear followers 15 and 16 are disposed within the yoke. The yoke and the parts therewithin are su i )orted in o )erative osition-b a de-l tachable saddle plate 17Y secured to the respective draft sills. The friction shell emmechanism is of the cylindrical lo. 35,100. Renewed-April 88, 1?.

ployed in connection with my improved t pe and in order to pro er1 center and'guidel` the same between the ra t sills a pair of guide plates 18-18 are disposed onl opposite sides of the shell, the plates being suitably secured tothe corresponding draft sills.

My improved shock absorbing mechanism proper, comprises broadly, a combinedl friction shell and spring cage casting A; a main wedgg B; three friction wedge-shoes C, D and two sets of friction lates E and F; a main `spring resistance a spring fol-. lower sleeve H; and a-retainer bolt J.

The combined friction shell and spring cage is inthe form. of a substantially cyl-indrical casting having a transverse rear end wall, 19 adapted to co-operate with-the rear follower 16. The friction shell section 20 is formedat the forward end of the casting A, the spring cage proper being formed rearwardly thereof. The friction shell 20 has three interior inwardly converging true cylindrical friction surfaces 21-21.'

The wedge B is in the form of a relatively heavy cored block, having a transverse flat` front end face 22 adapted to bear on the inner side of the front follower 15. The inner end of the block B has three rearwardly converfging wedge faces 23, 24, and 24, the three aces being symmetrically a`rranged around the axis of the mechanism. The faces 24 are disposed at relatively blunt an les with reference to thev longitudinal ams of the mechanism while the face 23 is disposed .at arelatively keen wedge acting angle'with reference to said axis. As most clearly shown in Figure 1, the wedge block B has a continuous annular laterally projecting flange 25 at the outer en'd thereof. The three friction shoes C, D and D are of like design, exceptas hereinafter ointed out. Each of the' shoes C, D and D as a longitudinally disposed outer. true cylindrical friction surface 26 adapted to co-operate with one of` the friction lates E. On theinner side, at they forwar end thereof, the shoe C has a wedge face 123 corresponding] inclined to an'd adapted to co-operate withl the wedge face 23 of the block B. The shoes D are eachalso provide-d with an inner wedge 'face at the forward end thereof, the same being indicated by 124. The'wedge faces 1M of the two shoes D co-operate with the faces 24 of the block B, being correure 4, eachl friction plate 'n 1 1',osa,oa4

spondingly inclined thereto. ItV will be evi-y dentv that the shoes D and D have their wedge faces `disposed at relatively blunt angles with reference to the longitudinal axis of the mechanism while the Shoe Chas its wedge face disposed at a relativelykeen wedge-acting angle with reference to said axis. U n

The two sets of friction plates E. and F are interposed betwen the wedge shoes andthe friction surfaces 21 of the shell. As most clearly shown n'Figures 1, 2 and4 3, the friction plates of the two sets are arranged in annular series, each set comprising three plates. The three lates E are all of like design, each plate ing curved in cross-section and having outer and inner true cylindrical friction surfaces, the inner friction surfaces'thereof co-operating with the friction surfaces 26 of the friction shoes.` Each of the lates E has a flange 27`lateral1 projecting t erefrom at the rear end. t will be evident that the flanges 27 of the three shoes E form a substantially complete annulus. The flanges 27 are adapted to work in an annular groove 28 provided on the interior wall of the friction shell, the opposite end Walls 29 and 30 of said groove limitin the outward and inward movement, respectively, ofthe plates E.

The friction plates F which are also three in number, are of like design. The

lates F are arranged in annular series simiarly to the plates E and are interposed between the latter and the friction surfaces 21 of the shell. As most clearlshown in Figis curved in transverse section and has inner and `outer true cylindrical frictionsurfaces adapted to co-operate respectively with the outer friction surfaces of one of the plates E and the corresponding friction surface 21 `of the shell. Each plate F is also provided with a lateral flange 31 at the forward end thereof, the flanges 31 of the three plates F forming a. substantially lcomplete annulus. The flange 31 of each plate F is adapted to bear on the outer end of the corresponding friction shoe. It will be seen that the plates F are thus positively returned tol their outermost position by the friction shoes.

, The main spring resistance element G comprises an outer relativel heavy coil 32- and a relatively lighter coil 33, the inner coil being of greater length ,than the outer coil. As most clearly shownv in Figure 1, the coil 32 bears at the rear end on the inner side of the end wall 19 of the 'spring cage. ends bearing respectively on transverse flat abutment faces 34 on the friction slices and the outer end of a hollow boss 35 projecting inwardly from the wall 19 of the spring,

ca e.

he sprin follower H is in the form of flange The coil 33 has its front and rear.

a cylindrical sleeve having a heavy annular the outer end lof the spring 32 bears. The front face of the flange 36 normally engages the, rear faces of the flanges 27 of the plates E.4 It `will be evident that .out\vard\inove )peut of the spring follower is thus limited by!V engement with the rear ends of the p tos ,outward movement of the latter being in turn limited by engagement of the flanges 27 thereof with the abutment face 29 of the 'friction shell.v As most clearly shown in Figure 1, a certain amount of clearance is provided between the inner ends of the friction shoes and the outer end of the spring follower sleeve H, thereby providing for a certain amount of relimina-ry action of the friction shoes. he opening Vlength by the retainer bolt J which has its 36 at the inner end thereof on which opposite ends anchored respectively to the main wedge B and the hollow boss 35 of the spring cage.

In the normal position of the parts which is that shown in Figure 1, the outer ends of the plates F are spaced from the inner face of t e annular flange 25 of the wedge -block yB, the distance between these parts preferably being greater `than the clearance vbetween the inner ends of the.friction shoes and the outer end of'the spring follower sleeve H. The spring 33 is preferably under initial compression, thereby providing for compensation for wear of the various friction and wedge faces of the mechanism.`

The spring 32 is also preferably under initial compression.

The operation of my improved shock absorbing mechanism durin a compression stroke is as followsz'The front follower 15 and the casting A are moved relatively toward each other, forcing the wedge B and the friction-shoes D-D inwardly of the shell, compressing the spring 33 and at the same time forcing the shoes apart, thereby lacing the friction plates E and F under ateral pressure and forcing the same Vagainst the friction surfaces of the shell.

During the initial inward movement of the follower 15 and the wedge B, there will be substantially no movement inwardly of the.

friction plates E and F, the spring 32 being of sufficient capacity to yieldingly maintain the plates in their outermost position. Dur

ing initial action, the friction shoes C, D and D lwill be forced to slide on the inwardly lcoi'iverging friction surfaces of the -,plates E. This action will continue until the inner ends of the shoes engage the spring follower H, thus starting compresi sion of coil 32. A slight additional com- .pression brings the flange 25 of the wedge and the friction shell. Inward movement of the two sets of plates and the friction shoes in unison will continue until the flanges 27 of the plates E enga e the abutment faces 30 ofthe casting A, whereupon movement of the plates E will be positively arrested. During the continued inward movement of the wedge B, the frictionvplates F will be forced to slide relatively to the plates E and the friction shoes will also slide on the last named plates. This action will continue until the'actuating pressure is reduced or the main follower 15 engages the outer end of the casting A, whereupon the actuatin force will be transmitted directly throug the latter to the follower 16, thereby preventing the springs from being driven solid.

It will be evident that there will be substantially no wedging action between the blunt faces of 'the wedge and the corresponding shoes, while a true wedging action will be effected between the co-operating keen yfaces of the wedge and the shoe C. Due to the converging relation of the friction shell surface and the consequent converging relation of the friction surfaces of the plates E, there will be a slight lateral approach of the friction shoes toward each other,'during compression of the mechanism, the blunt shoes slipping inwardly on the wedge faces of the mam wedge. Due to the differential action thus produced, there will be a slight additional compression of lthe coils.

32 and 33-of the main spring resistance. Durin the wedging action, there will also be a s ight expansion of the shell thereb storing up energy therein whereby the shel will forcibly contract when the actuating pressure is removed, creating lateral inward pressure on the blunt faced shoes and facilitating release of the main wedge due to the releasing angle of the co-o rating wedge faces of the main wedge an the shoes D.

In release, the springs 32 and 33 effectually restore all of the parts to normal position, the spring 33 forcing the shoes C and main wedge B outwardly until movement of the latter is limited by the retainer bolt J. The friction plates F will be carried outwardly in unison with `the shoes C, D and D,

limited by lthe abutment face 29.

By the employment of the blunt and keen sets of wedge faces, I am enabled to obtain l While I'ha-ve herein shown and described changes and modifications that come within the scope of the claims appended hereto.

I claim: l

1. In a friction shock absorbing mechanism, the combination with a friction shell; of a plurality of curved friction plates coo erating with the shell, certain of said p ates havingl limited movement with reference to the shell; an abutment face on t-he shell adapted to engage with the inner ends of said last named `plates for limiting the movement thereof while permitting further movement of the remaining plates; lateral wedge pressure-creating means co-operating with said plates; and a main spring resistance.

2. In a friction shock absorbing mechanism, the combination with a friction shell having interior curved friction surfaces: of an annular series` of curved friction plates within the shell, said plates and shell being adapted for limited relative movement; an abutment shoulder on the shell co-operating with the inner ends of said plates for limiting the movement thereof inwardly of tht` shell; a second annular series of curved friction plates interposed between the first named series and the friction surfaces of the shell; wedge-friction-shoes co-operating with said plates; a. main wedge co-operating with said shoes: and spring resistance means cooperating with said shoes and plates.

3. In a friction shockl absorbing mechanism, the combination with a friction'shell having interior friction surfaces: of a pluralitv of curved friction plates within the shell. said plates being held stationary during the initial compression of the mechanismv` all of said plates as a unit being adapted for bodily movement relative to said shell for a limited distance during a compression stroke; lateral Wedge pressure-creating mens frictionally co-operating with said plates and having relative movement to said plates and shellprior to movement of said plates with reference to the shell to provide for preliminary action during initial compression ofthe mechanism; 4means fixed with reference to the shell for arresting'vmovement of .certain of said plates at a predetermined point on the compression stroke of the mechanism and. thereafter permitting movement of the remaining plates relative thereto; and springvresistance means co-operating with said pressure-Creatin means and plates.

4. In a friction sliock absorbing mechanism, the combination with a friction shell having interiorl friction surfaces; of 'a fric-y tion Wedge system within said shell; sets of curved friction plates `interposed between saidwedge system and the friction surfaces of the shell,said setsof plates and wedge system being movable as a unit with reference to the shell during a predetermined portion of the compression stroke; means permitting relative movement between said wedge system land plates during the initial compression of the mechanism; abutment means on the shell for limitin ment of certain of saidplates a er said preldetermined compression and rmitting further movement of the remaining plates rela-- tive thereto during the remainder of the compression stroke; and spring resistance means co-operating with said wedge system` and friction plates.

5. In a friction shock absorbing mecha-`v nism, the combination witha friction shell@ having interior Vfriction surfaces converging'` a it inwardly of the mechanism; of a plur of curved `friction plates within the she?! and relatively movable thereto; co-operating means on said shell and certain of said plates e for limiting'relative movement thereof after .a predetermined compression of the mechanism while 'permitting further movement of the remaining plates; a lateral." pressure creatingy means (3o-operating with'saidplates i and having frictional engagement therewith, said lateral pressure creating means being movable with reference to said plates during initial compression of the mechanism; an spring resistance means, said means "maintaining the friction plates stationary with reference to the shell during said initial compression. Y L y 6. In a friction shock absorbing mechanism, the combinationwith a friction shell havinginterior friction surfacesgalurality of curved friction plates within t e shell;

pressure-transmitting means normally spaced shoes inwardly of they 'sh'` nism, the combination with ashel having the move-Ql Plates reference toL shellf'ldnring a predeterplates mwa ly o to be engaged there all of said plates and shoes being therea r movedv bodily inwardly of the shell as a unit during a further predetermined compression of the mechanism; fixed 'means kon l theshellA for arresting movement "of certain of yplates after said further compressionk of 'the mechanism vffwliilel: permitting movement of the ilatesfand lsaid v 1 u'ngthe further compression ofjY the .and spring jwresistance perating with said lates and shoes..,1

7. 5a friction shock absorbin mechainteriorffrietion surfaces; of aj plurality o friction plates within the shellga friction wedge system cio-operating with said'plates; spring means'co-operati n n saidy entirensystemiand 1 atea; i andga pressure transmitting sprin follower lmember interposed betweenv fsyste'mzand the springgmgans i with platesv fordtransmitting d fn i directly from sai ,stem-tosti' lilium;V means. 8.: aj frictionffshck mocha- "nisrn, 4the a) `fi-ictionshell l having interior) A`of a" plunii falco-0pm faction, am said ty* bodily-.gmbhas* fana .with

mined portion'. of compression stroke' means yieldi 1y op y the zshell; a* friction we -systemiincluding a 1 reading member and friction shoes, said ing with said plates;

"ng `increment of sa.'

oes co-operatring means resisting respectively with inward`-movementof said shoes; and pressure transmitting Ymeans' co-operating with said 'first named means,"said pressure means being normal] i spaced ,from said shoes and adapted to i 'engagedby the latter after a predetermined ooinpn of the mecha- I nism to transmit the actuatingv force from said i-st namedy means.l

9. In a friction shock absorbing mechansm, the combination with a friction shell; of a plurality of curved friction plates withinthe shell, said lates being movable bodily as a unit inward y of the shell during a predetermined compression of the mechanism;

vmeans for positively limiting inward movement with reference to the shell of certain of said plates to compel relative movement ment of said shoes and plates; and a spring resistance co-operating with said shoes.

10; In a friction shock absorbing mechaanism, `the combination with a friction shell; of a plurality of friction plates within the shell, said plates being adapted for relative movement and certain of said plates having limited movement with reference to the shell; pressure-transmitting means normally spaced from the remaining plates and adapted to engage the latter after a predetermined compression of the mechanism and move the same inwardly of the shell; a spring resistance; follower-acting means interposed between said spring resistance and plates; a wedge movable with-said pressure-transmitting means; wedge-friction-shoes co-operating with the wedge and pla-tes, said shoes having their inner ends normally spaced from said spring follower and adapted toengage said 4spring' follower during the compression stroke of the mechanism, and a second spring resistance co-operating with said shoes. Y

11. In a friction shock absorbing mechanism, the combination with a friction Vshell having inwardly converging friction sur-v faces, said surfaces being curved transversely; of a circular series of curved plates co-operating with said shell friction sur'- faces; asecond circular series of curved plates frictionally co-operating with said first named plates; means on said shell for limiting the movement of said last named plates with lreference thereto; wedge-fric* tion-shoes co-operating with said-'last named I plates; means on said first named plates engaged by said shoes for restoring the plates to normal position during release of the mechanism; and spring resistance means cooperating with said shoes and second named plates.

12. In a friction shock absorbing mechanism, the combination with front and rear p lgitudinal movement with reference to the shell; means for arresting movement of said last nam-ed plates after. a predetermined compression of the mechanism, the remaining plates being thereafter movable with reference to the shell and said arrested plates; wedge pressure-creating means for placing said annular sets of plates under lateral pressure; spring resistance means operatively associated with said Wedge-pressure creating means; a second spring resistance means co-operating with said plates and pressure-transmitting means interposed between said last named spring means and friction shoes.

yIn witness that I claim the foregoing I have hereunto subscribed my name this 29th day of May 1925.

i. JOHN F. OCONNOR. 

